With a major focus on online play, there's no story at all here - all you have to do is pick a team, and a character, before facing off in a battle with another team of players. With a handful of modes to choose from, from an outright "team deathmatch", where two teams race to be the first to 50 kills, or a slightly more strategic "defend your territory" mode, where you have to either defend, or assault a position, each mode plays out in a pretty similar way. With each character having their own strengths and weaknesses (some are fast but weak, others are powerful but slow), there's an emphasis on team work here, and a character to suit every play style. Those who work best as a team tend to come out on top, which is a pretty positive reinforcement.
Sadly, though, for those who prefer to play in single player, there's very little to speak of here, with only a single game mode that's playable on your own, against computer controlled players. For everything else the game has to offer, you'll have to head online and play against real people - which makes giving this game an age rating for difficulty somewhat tricky, as it really depends who you're playing against.
While the Xbox One version of the game has an "exclusive" split-screen mode, this too only allows you to play a single game type, and only lets you play offline, rather than letting you take a friend with you to venture online - and even this offline split-screen mode requires an Xbox Live Gold subscription.
In terms of things children may struggle with, so long as they're proficient at dual analogue controls, Garden Warfare should present few problems. For those less experienced with shooters, though, this isn't the easiest of games to get the hang of. With no tutorial to explain the basic controls, and no single player mode you can use to polish up your skills (after all - you can't set the difficulty level online), this could be a tricky one for younger players.
While some of the zombies do have a tendency to fall apart when they're defeated, as there's no blood in sight, this is one of the most family friendly shooters you'll find.